Foldable Sandblasting Cabinet

ABSTRACT

A collapsible sand blasting cabinet comprising a folding frame ( 10 ), the folding frame comprising a base ( 1000 ), a plurality of legs ( 1110 ) pivotally mounted to the base, a front frame ( 1200 ) pivotally mounted above the front of the base, a rear frame ( 1300 ) pivotally mounted above the rear of the base, a flexible enclosure ( 20 ) attached to the said folding frame in a way which allows internal access through the front frame, a perforated floor ( 3160 ) attached to the said base sandwiching the enclosure, and, a removable door adapted to seal said flexible enclosure at the front frame. The plurality of legs may comprise of two sets of legs that are hingedly mounted to the base. The front frame may comprise of a top section ( 1200   b ) and a bottom section ( 1200   a ), the top and bottom sections meeting at an angle of between 90 degrees and 180 degrees. The rear frame may comprise of an upper ( 1320 ) and a lower ( 1310 ) section, the sections being hingedly joined. The enclosure preferably includes a hopper ( 2200 ) and is composed of PVC.

BACKGROUND OF THE INVENTION

The present invention relates to a sandblasting cabinet assembly whichis collapsible, lightweight and portable while still having a largeworking volume.

Sandblasting is a well known operation where a pressurized fluid medium,such as air or water, has an abrasive medium introduced into it and isdirected at a work piece. The effect of this process is to abrasivelyclean the work piece.

Abrasive blasting can be performed in an open uncontained environment.In this operation there are several problems including the abrasive andwaste dust creating a “dust storm” necessitating the need to wearprotective clothing and the use of breathing apparatus, polluting theenvironment. Further in an open uncontained environment this is a totalloss system meaning that the once abrasive is used it cannot be reused.

Because of these problems sealed cabinets have been used to contain thework piece. These cabinets are typically constructed from sheetmaterials and have an enclosure with an inbuilt hopper, a perforated ormesh floor to support the work piece, an access door, a viewing portal,a pair of apertures to which gloves are connected so the operator canhandle the work piece, a connection for a dust extractor, a vent torelieve internal pressure (created by the dust extractor), a valve toremove spent abrasives and an abrasive blasting gun to carry out theoperation.

Most available cabinets are made of sheet metal and are of a weldedconstruction. They vary in size and cost, with the largest being manythousands of dollars and able to handle very large work pieces and thesmallest bench top units costing several hundred dollars but havinglittle useful work volume. Because of their size, larger more usefulcabinets have been very expensive to buy as distribution costs become amajor part of the cabinet's cost. Additionally, they occupy asignificant amount of floor space and they are not easily moved betweendifferent sites. This is of particular concern in environments wheresandblasting is not carried out on a continual basis.

Sandblasting cabinet assemblies have been proposed which can be nondestructively disassembled or collapsed via a folding frame however theyeither take too long to disassemble or when collapsed are stillrelatively large.

It is an object of the present invention to overcome or ameliorate theproblems seen in the prior art, or to at least provide an alternative.

The term “comprising” and its grammatical variations as used herein, isused in the inclusive sense of “having” or “including” and not in theexclusive sense of “consisting only of”.

SUMMARY OF THE INVENTION

According to a first aspect of the invention, there is provided acollapsible sand blasting cabinet comprising a folding frame, thefolding frame comprising a base, a plurality of legs pivotally mountedto the base, a front frame pivotally mounted above the front of thebase, a rear frame pivotally mounted above the rear of the base, aflexible enclosure attached to the said folding frame in a way whichallows internal access through the front frame, a perforated floorattached to the said base sandwiching the enclosure, and, a removabledoor adapted to seal said flexible enclosure at the front frame.

Preferably the plurality of legs comprises two sets of legs that arehingedly mounted to the base.

Preferably the front frame comprises a top section and a bottom section,the top and bottom sections meeting at an angle of between 90 degreesand 180 degrees.

Preferably the rear frame comprises an upper and a lower section, thesections being hingedly joined.

The enclosure is preferably includes a hopper and is composed of PVC.

Preferably the door is fastened to the front frame using fasteningmeans, including retaining strips.

Preferably the door includes a viewing portal and two apertures, theapertures being adapted to have gloves inserted therethrough. The glovesare preferably composed of abrasion resistant material.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows a perspective view of a sandblasting cabinet in accordancewith the preferred embodiment.

FIG. 2 shows an exploded view of a sandblasting cabinet in accordancewith the preferred embodiment.

BEST MODE OF CARRYING OUT THE INVENTION

The preferred embodiment of the sandblasting cabinet assembly of thepresent invention can be seen by referring to the drawings FIG. 1 & FIG.2.

By reference to FIGS. 1 and 2 the folding frame 10 has a base frame1000, left and right legs 1110L & 1110R, front frame 1200 and rear frame1300. Base frame 1000 is composed of a rectangular or square metalsectioned tube 1115 which is bent to form the required frame shape asshown then welded to close the loop. Other parts will be attached to thebase frame to perform other functions and details of these will bedescribed in their relevant sections.

Attached to each side of the base frame 1000 are left and right legs1110L and 1110R. These are also formed from rectangular or square metaltube to the required shape as shown. Legs 1110L and 1110R alsoincorporate a cross bar 1112, which acts to increase the leg stability.Crossbar 1112 is positioned so it also has the additional function ofproviding a pivotal stop for leg brace 1130 when the legs are folded up.Legs 1110L and 1110R are pivotally connected to the base frame 1000.Hinges 1010 are fixed to the inner vertical face of the legs and frame.The pivot point of the hinges 1010 is located so that the effect ofpivoting the legs 1110L and 1110R is to move them away from the baseframe 1000 to provide clearance between said legs 1110L and 1110R andbase frame 1000. This clearance improves the nesting of the legs 1110Land 1110R when they are folded.

Leg brace 1130 comprises a pair of supports 1131 which on one end arepivotally connected to the legs 1110L & 1110R using pins or fasteners1140. The other end of the leg brace 1130 has slots which are engagedinto threaded studs 1030 secured in the base frame 1000 which are thensecured with nuts or wing nuts (not illustrated) to hold the legs 1110L& 1110R in the open position. Leg brace 1130 is also cross-braced toincrease stability. The leg braces 1130 are placed to clear the hopperportion of the enclosure assembly.

Attached above the front of the base frame 1000 is the front frame 1200.This is also formed from rectangular or square metal tube and is formedinto two substantially ‘U’ shaped sections 1200 a (lower) and 1200 b(upper), which are welded to form a bend 1205 of between 90 and 180degrees approximately in the center of the front frame 1200. The purposeof the bend 1205 is to change the angle of the viewing portal 4200 sothe operator's line of sight is directed towards the work piece (notillustrated). The front frame 1200 is pivotally connected to the baseframe 1000 using hinges 1040. The hinge 1040 is connected to the frontvertical face of the base frame 1000. The hinge 1040 is also fastened tothe bottom of the front frame 1200. This connection sandwiches the frontedge of the enclosure, the front lower enclosure retaining strip 1211and the door lower retaining bracket 1230. Front frame 1200 is held inthe opened position by front frame stays 1280.

Attached above the rear of the base frame 1000 is the rear frameassembly 1300. This is also formed from rectangular or square metal tubeformed into two substantially ‘U’ shaped sections 1310 (lower rearframe) and 1320 (upper rear frame), which are pivotally connectedapproximately in the center of the rear frame assembly 1300. The pivotbetween frames 1310 and 1320 is a pin with a loop formed on one end1330. Lower rear frame 1310 is pivotally connected to the base frame1000 using hinges 1050. The hinge 1050 is connected to the rear of thebase frame 1000 and connected to the bottom of the rear lower frame1310. Rear frame assembly 1300 tensions the enclosure system and finaltensioning is achieved using tensioning stays 1340 which are locatedapproximately halfway up the upper rear frame 1320. After the frontframe 1200 has been locked into position with front frame stays 1280,the rear frame assembly 1300, the enclosure 20 and the tensioning stays1340 work in unison to tension the enclosure.

The structural combination of the legs 1110L & 1110R with the base frame1000, the front frame 1200 with the base frame 1000 and the lower rearframe 1310 with the base frame 1000 increase the strength and stabilityof the frame assembly 10 by doubling up the material section strength oneach edge of the base frame's edges resulting in a frame assembly 10that is strong, lightweight and simple to manufacture.

The enclosure assembly 20 in conjunction with the frame 10 and door 40forms a sealed volume so the operator can perform the sandblasting taskwhile keeping the dust and contaminants within the enclosure assembly20. As illustrated the assembly 20 contains an almost rectangularworking upper volume 2100 defined by the extents of the front frame 1200and rear frame 1300 above the base frame 1000. The enclosure assembly 20also contains a funnel shaped hopper 2200, which hangs below the baseframe 1000 for the purpose of collecting and recycling the blast media.Below the hopper 2200 there is a pocket 2300, which has an opening flap2310, which is used to remove the blast media from the enclosureassembly 20. The enclosure assembly 20 is fixed to the edges of thefront frame 1200 using retaining strips 1211 and 1221 and the edge ofthe upper rear frame 1320 using retaining strips 1350. It is alsoattached to perimeter of the base frame 1000 by being sandwiched inbetween the base frame 1000 and the floor frame 40.

The upper section 2100 comprises a back wall 2101, left side wall 2102,right sidewall 2103 and a top wall 2104. A vacuum port 2107 is providedin one or more of the upper wall sections so a dust extractor can beattached to the enclosure. Port 2107 is composed of a flexible sheetwith a central aperture secured to one of the walls. It can be seen thatthe flexibility will allow different sized vacuum nozzles to be insertedinto the enclosure assembly 20. Enclosure tensioner lugs 2105 areincorporated on side walls of 2100 and a tensioning cord 2400 isfastened to each of these through the loops of the pins 1330 in the rearframe 1300. The tensioner ensures the rear frame 1300 and enclosure 20collapses inwards when tensioning stays 1340 are released and enclosureside walls 2100 remain in tension and do not get caught in tensioningstays 1340 or rear frame 1300 as the frame is folding.

The lower section 2200 is an inverted pyramid shaped funnel. Attached tothe bottom of the lower part of the funnel is a tubular pocket 2300which can be closed off at its end for removal of blast media and waste.

The enclosure 20 is composed from a material which is lightweight,flexible, abrasion resistant and easily repairable, such as PVC.

A vent hole 2106 is disposed in the upper section 2100. The vent hole2106 will also be provided with a chute 2108 leading to it to minimizedust seeping out the vent 2106.

The floor assembly 30 consists of a frame 3100, which follows the shapeof the base frame 1000 and has a mesh floor 3160 attached to the top ofthe frame. Depending on the size of the frame it may have cross supportsto increase the stiffness of the mesh 3160. An opening 3105 is includedin the assembly so the blast media feed pipe (not illustrated) can beinserted into the blast media (not illustrated) in the hopper 2200 andto retrieve small objects, which may fall through the mesh. The opening3105 could optionally have a closing door. Introduction of compressedair into the sandblasting cabinet 1 is via fittings 3210 fastened to theframe 3100 in one of the corners however this connection could be madedirectly into any part of the enclosure 20 or the door assembly 40. Thefloor assembly 30 is fastened to the base frame 1000 with enclosure 20sandwiched in-between these two parts.

The cabinet is closed off by the door assembly 40, which is secured inan openable fashion to the front frame 1200. The door assembly issecured by putting the lower edge of the door assembly 40 into the doorretaining brackets 1230 and locking the door closed with toggle catch1240 however other forms of fastening or variations in design such ashinging the door or using toggle catches around the perimeter could beused.

The door 40 follows the shape of the front frame 1200 with a flange thatfollows the external edge of the front frame 20. A seal 1250 is attachedto the edge of the front frame 1200 and provides a seal between the door40 and frame 10 and enclosure assembly 20 so dust is kept within theunit. The upper portion of the door 40 is supplied with an aperture 4201which carries a viewing window 4200 and the lower portion of the door 40includes a pair of apertures 4202 which have flanges 4203 around them towhich are attached the abrasion resistant gloves 4410 and gloveextensions 4420. The gloves are composed of thick rubber or otherabrasion resistant material. The viewing window 4200 is supplied so theoperator can view the article being abraded and the gloves 4410 areprovided so the operator can manipulate the article. The bent shape inthe door 40 is provided so the operator's line of sight is directed downtowards the area where the article will be held. The glove extensions4420 are supplied as an extension of the gloves 4410 to allow theoperator to reach all areas of the cabinet 1. The glove extensions 4420are made of a filter fabric so that internal pressure will be relievedwhen a vacuum is applied to extract the dust.

While the above detailed description generally describes the preferredembodiment of the invention it should be noted that variations of detaildesign, material selections, manufacturing methods and configuration arepossible within the spirit of the invention.

It is envisaged that other methods could be employed to hold the legs inan opened position. For example, folding table stays or other methodscould be used to fasten the top brace 1130 to the base 1000.

The legs could be individual removable legs or a separate removableassembly.

The frame components of the base frame 1000, legs 1110L and 1110R, frontframe 1200 and rear frame parts 1310 & 1320 could also be made withwelded corner joints rather than bends or all parts could be molded fromsome type of plastic.

The flexible port 2107 could be replaced with fixed sized nozzles (notillustrated) constructed from solid materials with appropriate adaptersto achieve the same result.

The top wall of 2100 or the entire enclosure could be made of atransparent material so that the interior of the enclosure would be welllit so an internal light would not be necessary. In an alternateembodiment of the invention parts of the fabric enclosure could be madefrom a breathable filter fabric to relieve internal pressures due to theuse of a dust collecting vacuum. It should be noted that this inventionshould not be restricted to the venting methods described rather to theneed to vent the enclosure while minimizing dust escaping.

1. A collapsible sand blasting cabinet comprising: a folding frame, thefolding frame comprising a base, a plurality of legs pivotally mountedto the base, a front frame pivotally mounted above the front of thebase, a rear frame pivotally mounted above the rear of the base, aflexible enclosure, the enclosure is attached to the perimeter of thefront frame, to the rear frame and to the perimeter of the base. aremovable door adapted to seal said flexible enclosure at the frontframe. a perforated floor attached to the base frame inside the flexibleenclosure.
 2. A collapsible sand blasting cabinet as defined in claim 1,wherein the plurality of legs comprises two sets of legs that arehingedly mounted to the base.
 3. A collapsible sand blasting cabinet asdefined in claim 1, wherein the front frame comprises a top section anda bottom section, the top and bottom sections meeting at an angle ofbetween 90 degrees and 180 degrees.
 4. A collapsible sand blastingcabinet as defined in claim 1, wherein the rear frame comprises an upperand a lower section, the sections being hingedly joined.
 5. Acollapsible sand blasting cabinet as defined in claim 1, wherein theenclosure includes a hopper.
 6. A collapsible sand blasting cabinet asdefined in claim 5, wherein the enclosure is composed of PVC.
 7. Acollapsible sand blasting cabinet as defined in claim 1, wherein thedoor is fastened to the front frame using fastening means, includingretaining strips (1211).
 8. A collapsible sand blasting cabinet asdefined in claim 7, wherein the door includes a viewing portal.
 9. Acollapsible sand blasting cabinet as defined in claim 8, wherein thedoor includes two apertures, the apertures being adapted to have glovesinserted therethrough.
 10. A collapsible sand blasting cabinet asdefined in claim 9, wherein the gloves are composed of abrasionresistant material.
 11. A collapsible sand blasting cabinet according toclaim 1 wherein the front frame and the rear frame are foldable onto thetop surface of the base along the respective pivotal mountings on thebase, the flexible enclosure being foldable as well by the rear andfront frames' collapse; and the plurality of legs are foldable onto thebottom surface of the base.
 12. Any one or combination of the parts of acollapsible sand blasting cabinet according to claim 1 in assembled orunassembled configuration.